"Metallodendrimers of Nickel: Preparation and evaluation as catalyst precursors in the transformation of unsaturated hydrocarbons”

by

Prof. Selwyn F. Mapolie

(Department of Chemistry and Polymer Science, Stellenbosch University,    [email protected])

When:            Wednesday, 28 September 2011

Time:             11:30 - 12:30

Venue:          The Avogadro – Old Chemistry

Abstract: 

Metallodendrimers are dendritic macromolecules into which metal centres are incorporated at different possible positions, such as the periphery, the core or branches of the dendrimer. The application of metallodendrimers as catalyst precursors in a range of organic reactions has received increasing attention over the last couple of years.   This include work reported by our research group where we have been focussing on diamino butane (DAB) cored polypropylene imine dendrimers. We have however recently also embarked on a project to develop new metallodendrimers based on macrocyclic cores. This talk highlights some of our recent work on the development of new metallodendrimers of nickel including the new cyclam-cored dendrimers. These metallodendrimers have been employed as catalyst precursors in the oligomerization of ethylene using EtCl₂Al as co-catalyst as well as in the polymerization of norbornene to produce polynorbornene. In both processes we observed a clear dendritic effect with both activity and selectivity being impacted by the dendrimer type and dendrimer generation.   Some of our main results will be presented in this talk.